package gitapp.oschina.net.my_osc.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.ImageView;

import gitapp.oschina.net.my_osc.R;

/**
 * @author Tristan-Hou
 */
public class CircleImageView extends ImageView{
    private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;

    private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;
    private static final int COLORDRAWABLE_DIMENSION = 1;

    private static final int DEFAYLT_BORDER_WIDTH = 0;
    private static final int DEFAULT_BORDER_COLOR = Color.BLACK;

    private final RectF mDrawableRect = new RectF();
    private final RectF mBorderRect = new RectF();

    private final Matrix mShaderMatrix = new Matrix();
    private final Paint mBitmapPaint = new Paint();
    private final Paint mBorderPaint = new Paint();

    private int mBorderColor = DEFAULT_BORDER_COLOR;
    private int mBorderWidth = DEFAYLT_BORDER_WIDTH;

    private Bitmap mBitmap;
    private BitmapShader mBitmapShader;
    private int mBitmapWidth;
    private int mBitmapHeight;

    private float mDrawableRadius;
    private float mBorderRadius;

    private boolean mReady;
    private boolean mSetupPending;
    public CircleImageView(Context context) {
        super(context);
    }

    public CircleImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CircleImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        super.setScaleType(SCALE_TYPE);
        TypedArray typeArray = context.obtainStyledAttributes(attrs,
                R.styleable.CircleImageView, defStyleAttr, 0);
        typeArray.getDimensionPixelOffset(R.styleable.CircleImageView_border_width, DEFAYLT_BORDER_WIDTH);
        typeArray.getColor(R.styleable.CircleImageView_border_color, DEFAULT_BORDER_COLOR);
        typeArray.recycle();

        mReady = true;
        if(mSetupPending){
            setup();
            mSetupPending = false;
        }

    }

    @Override
    public ScaleType getScaleType(){
        return SCALE_TYPE;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (getDrawable() == null){
            return;
        }
        canvas.drawCircle(getWidth()/2, getHeight()/2, mDrawableRadius, mBitmapPaint);
        if (mBorderWidth != 0){
            canvas.drawCircle(getWidth()/2, getHeight()/2, mBorderRadius, mBorderPaint);
        }
    }

    @Override
    public void setScaleType(ScaleType scaleType){
        if (scaleType != SCALE_TYPE){
            throw new IllegalArgumentException(
                    String.format("ScaleType %s not supported", scaleType));
        }
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh){
        super.onSizeChanged(w, h, oldw, oldh);
        setup();
    }

    @Override
    public void setImageResource(int resId) {
        super.setImageResource(resId);
        mBitmap = getBiemapFromDrawable(getDrawable());
        setup();
    }

    /**
     * Sets a drawable as the content of this ImageView.
     *
     * @param drawable the Drawable to set, or {@code null} to clear the
     *                 content
     */
    @Override
    public void setImageDrawable(Drawable drawable) {
        super.setImageDrawable(drawable);
        mBitmap = getBiemapFromDrawable(drawable);
        setup();
    }

    /**
     * Sets a Bitmap as the content of this ImageView.
     *
     * @param bm The bitmap to set
     */
    @Override
    public void setImageBitmap(Bitmap bm) {
        super.setImageBitmap(bm);
        mBitmap = bm;
        setup();
    }


    private Bitmap getBiemapFromDrawable(Drawable drawable){
        if (drawable == null){
            return null;
        }
        if (drawable instanceof BitmapDrawable){
            return ((BitmapDrawable)drawable).getBitmap();
        }

        try {
            Bitmap bitmap;
            if (drawable instanceof ColorDrawable){
                bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION,
                        COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);
            }else {
                bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
                        drawable.getIntrinsicHeight(), BITMAP_CONFIG);
            }
            Canvas canvas = new Canvas(bitmap);
            drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
            drawable.draw(canvas);
            return bitmap;
        }catch (OutOfMemoryError e){
            return null;
        }

    }

    private void setup(){
        if(!mReady){
            mSetupPending = true;
            return;
        }
        if (mBitmap==null){
            return;
        }
        mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
        mBitmapPaint.setAntiAlias(true);
        mBitmapPaint.setShader(mBitmapShader);

        mBorderPaint.setStyle(Paint.Style.STROKE);
        mBorderPaint.setAntiAlias(true);
        mBorderPaint.setColor(mBorderColor);
        mBorderPaint.setStrokeWidth(mBorderWidth);

        mBitmapHeight = mBitmap.getHeight();
        mBitmapWidth = mBitmap.getWidth();

        mBorderRect.set(0, 0, getWidth(), getHeight());
        mBorderRadius = Math.min((mBorderRect.height()-mBorderWidth)/2,
                (mBorderRect.width()-mBorderWidth)/2);

        mDrawableRect.set(mBorderWidth, mBorderWidth,
                mBorderRect.width()-mBorderWidth, mBorderRect.height()-mBorderWidth);
        mDrawableRadius = Math.min(mDrawableRect.height()/2, mDrawableRect.width()/2);

        updateShaderMatrix();
        invalidate();
    }

    private void updateShaderMatrix(){
        float scale;
        float dx = 0;
        float dy = 0;

        if (mBitmapWidth*mDrawableRect.height() > mBitmapHeight*mDrawableRect.width()){
            scale = mDrawableRect.height() / mBitmapHeight;
            dx = (mDrawableRect.width() - mBitmapWidth*scale)*0.5f;
        }else {
            scale = mDrawableRect.width() / (float) mBitmapWidth;
            dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;
        }
        mShaderMatrix.setScale(scale, scale);
        mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth, (int) (dy + 0.5f) + mBorderWidth);
        mBitmapShader.setLocalMatrix(mShaderMatrix);

    }

}
